Pulse delay circuit



June 14, 1960 J, HARRICK 2,941,092

PULSE DELAY CIRCUIT Filed Oct. 25, 1955 INPUT ye PULSE f- SOURCE FL SWEEPING 48 PULSE t SOURCE F/gQ/ 27 28 15 I 29 s -U ,2 3| s2 9' l9' INPUT 1 PULSE SOURCE 2 SWEEPING PULSE SOURCE 2 INVENTOR NICOLAS J. HARRICK AGE flush with the surfaces thereof. a I .sistance terminals 10 and 11 at its opposite endsftermed the base electrodes, which may be, for example, coatings of rhodium on said body.

PULSE DELAY CIRCUIT Nicolas J. Harrick, North Tarrytown, N.Y., assignmto North American Philips Company, Inc.

Filed Oct. 25, 1955, Ser. No. 542,657 12 Claims, (Cl. 307-485) The present invention concerns pulse delay circuits of the type utilizing semiconductor signal translating devices with controlled carrier transit times. More particularly, the present invention concerns multipulse delay circuits of the type utilizing semiconductor signal translating devices with controlled carrier transit times.

The principal object of the present invention is the provision of a multipulse delay circuit utilizing a semiconductor signal translating device. An object of the present invention is the provision of a multipulse delay circuit utilizing a semiconductor signal translating device which produces a pulse of suitably high amplitude.

Another object of the present invention is the provision of a multipulse delay circuit utilizing a semiconductor signal translating device having independently controlled amplitude and delay time.

A further object of the present invention is the provision of a multipulse delay circuit of compact nature and etficient operation.

These and other objects and features of the invention will be apparent from a consideration of the following detailed description taken in connection with the accompanying drawing, wherein:

Fig. l is a schematic diagram of a preferred embodiment of the pulse delay circuit of the present invention; and

Fig. 2 is a schematic diagram of another embodiment 'ample, of N conductivity type germanium produced by adding thereto minute impurity levels of antimony, arsenic, bismuth, or the like, in a manner well known in the art. The zones 2, 3, 4 and 5 and the junctions 6, 7, 8 and 9 may be produced by alloying the body 1 at suitable points with suitable metals such as indium, gallium, or the like, in a manner well known in the art. Said zones preferably protrude from said body, although they may be The body 1 has low re- A plurality of contacts 12, 13 and 14 bear against the zones 2, 3 and 4, respectively, on one surface of the body 1. Said contacts may, for instance, be soldered to said zones to keep them from slipping. A coutactlS bears against the zone 5 on the opposite surface of the bodyi. Said contacts may be,-for example, of nickel or-copp'er. The contacts 12, 13 and 14 function as emitter electrodes and are biased in the forward direction by an input pulse "source 16 which isconnected between a common junction 17 of said emitter electrodes an g ou d. The input pulse source 16 is conventional in form and may consist,

for example, of a multivibrator, the pulses of which are to be delayed. The contact 15 functions as a collector electrode and is biased in the reverse direction by a sweeping pulse source 18 which is connected in series with the base electrodes 10 and 11; the primary purpose of the source 18 being to sweep carriers through the body 1. The pulse source 18 may be conventional in form and may consist of a well known multivibrator, the constants of which are appropriately selected so that the occurrence of the pulse occurs at least immediately prior to the occurrence of the pulse from the source 16 and the duration is at least equal to the desired delay period of the connection so that they operate in the desired synchro-' msrn.

The series connection of the source 18 and the base electrodes 10 and 11 is grounded between the source 18 and the base electrode 11. The collector electrode 15 is grounded through a load resistor 19, across which the desired delayed output pulses are produced. The input pulse source 16 feeds a pulse to the emitter electrodes through input terminals 20 and 21. The output pulses are removed through output terminals 22 and 23 across the load resistor 19.

A variable input impedance such as a variable resistor 24 is connected in series in the circuit of the emitter electrode'12 between said emitter electrode and the common junction 17; a variable input impedance 25 is connected in series in the circuit of the emitter electrode 13 between said emitter electrode and the common junction 17; and a variable input impedance 26 is connected in series in the circuit of the emitter electrode 14 between said emitter electrode and the common junction 17. Of the impedances 24, 25 and 26, the impedance of 24 is preferably the smallest, relatively, the impedance of 25 is larger, relatively, than that of 24, and the impedance of 26 is the largest, relatively.

The output voltage produced at the output terminals 22 and 23 is a series of pulses superimposed upon the pulse provided by the sweeping pulse source 18. The series of superimposed output pulses correspond to the input pulses provided by the input pulse source 16. The

relative amplitudes of the pulses of said series may be adjusted by adjusting the input impedances 24, 25 and 26 said time delay tending to increase as said spacing is increased.

Fig. 2 is a schematic diagram of another embodiment of the pulse delay circuit of the present invention. Fig.

2 is similar to Fig. 1 except for the number of emitter and collector electrodes. In Fig.2, semiconductor body 1', zones 2' and, 5, PN junctions 6' and 9, end terminals 10' and 11, point contacts 12' and 15', input pulse source 16', sweeping pulse source 18, load resistor 19', input terminals 20 and 21',-and output terminals 22' and 23,

all correspond with, are connected as, and operate to- .gether as their counterparts of Fig. 1.

In the embodimeent of Fig. 2, however, a plurality of lcollector electrodes is connected through a common junction to ground through the load resistor 19' and only'a single emitter electrode is provided. Contacts 27, 28 and 15' comprise the collector eelectrodes and contact oppositeconductivity zones 29, 30 and 5', respectively,

which fonm PN junctions or barriers spectively, with body-1.

A variable input impedance 33 is connected in series 31, 32 and 9', re-

in the'lcircuit of the collector electrode 27 between said Of the impedances 33, 35 and 3d, the impedance 33 is preferably the largest, relatively, the impedance of 35 :is smaller, relatively, thanthat of 33, and the impedance of 36 is the smallest, relatively. I

The output voltage produced at the output terminals 22 and}? is a series of pulses superimposed upon the pulse providedby the sweeping -pulse source 18'. The series of superimposed output pulses correspond to the input pulses provided by the input pulse source 16. .Therelative amplitudes ofthe pulses of said series vary w th t e pu i a e 31 5 an .3 ft jwl e tq electrodes 2'7, 28 and 15', respectively; each pulse of said series vcorresponding to one of said collector electrodes The time delay between adjacent pulses of said series varies with the relative spacing of the corresponding collector electrodes and the emitter electrode 12", said time delay tending to increase as said spacing is i re s dor i ,q The use of alloyed junctions rather than pointcontaets with the body 1, permitsthe amplitudes of the series of output pulses to be high enough for practical; purposes. Point contacts'are found to produce output pulses which are too -small in; amplitude for practical purposes. For 1 .1-i he ,,1-r utrut pulse .--am imde a trans erse. m neti fi ld m b u z d ,d emsu1 a wmm ra ie 9 carr er lathe c n ygoif. t e c l e q r lestmde and due to theguiding of carriers, through the bulk ofithe hody 1 to thereby reduce the eflects of surface recomna n a. 7., t r V The sweeping pulse source 18 is utilized to avoid the adverse heating effects that a continuous 'D.C. would have on the body 1.

1 n theembodiments of Figs. land 2, the body l was selected of N conductivity typernaterial suchas gerrnanium and the zonesZ, 3g, 4 and 5, and 1, 29, 30 and 5" were selected of P conductivity type material such-as indium, It is obvious that a body of P conductivity t e-m e i m y b utilized. w th. 199%....9LN n99 ,ductivity material if the bias source polarities are suitably changedinarnanner known in the art.

his to be understood that the invention fi not; limited tothe details disclosed but includes all SLiOh variations and modifications as fall within the spirit of theinvention andthe scope of the appended claims W J ,v Having thus set forth the nature of my invention, what I claim is:

C 1. A pulsejdelay circuit -including a signal translation device comprising an elongated body of semiconductive material of predetermined conductivity type having opposite end portions and surface portions between said end portions, a plurality of zones ofimaterial of opposite conductivity type spaced apart and arranged on said surface portions, first electrode means in contact with two of said zones, "second "electrode rne'ans in contact with one of said zenesgspaeee item :sa'id two zones, and apair of base fele'ctrode's inlow "resistance-contact with "said opposite end portionsfa first pulse signal source lconnected'it'o one: of said "electrode Pul i' l.

means, a second r a in r *an ouput signal e'omprisin a series fof' "ulss c freondi ngt'o theipulsesiprovidedfby'saidi al t lsu r edaao ;.ihg pvl g zi i n second pulse signal source, the time of occurrenee 'of 12 4 9; .:-said se e o pul es fter th l-imt a pn j produced by said' -firstpulse signal *source accordance with the relat-ve spacing of said first and second electrode means. a

2. A pulse delay circuit as claimed in claim 1, further including means connected to one of said electrode means 5 for varying the amplitude of the output signal pulses, and wherein the pulses of said series of pulses have relative amplitudes determinedby the said amplitude varying means I t g I 3. A pulse dang e-innit as-clainiedin -claim 2, wherein .saidra rnplitudevaryingmeans comprises variable w a. 1 .4 a,

4. A pulse delay circuit including a signal translation device comprising-an elongated body of s'erniconductive material of predetermined -conductivity type having op- 15 posite end portions'andsur'face portions between said end portions, a plurality of zones of material of opposite conductivity type spaced apart and arranged on said surface portions, first electrode means in contact with at least two of .saidzone's, second electrode means .in

contact Wit'hQone o fsa'id zone's spaced "apart from said firstementionedjzones, and ap'a'ir 'of base electrodes in low resistance contact with said opposite end portions, a

surprisesiganso tree'eeansctea to said .first electrode means, a second .piilse'signal -source connected to said electrodes; and output pulse "deriving means connect'ed tosaid second elect-rode means providing an out- ;put signal comprising a series of pulses corresponding to the; pulses l'provide'd hyjsa'id'fi rst pulse signal .source superimposed upon the pulse provided by said second pulse signal source, the firn'eof occurrence ofeach pulse of said series of pulses after the initial pulse jproduced "by the' sa'id first purse signal son'ree varying 'in accomance with the 'rel'ati ve'spacing of said first and'second electrode means. 7

5. A pulse delaycircuitas claimed in claim 4, further comprisin meaas interposed between said first pulse signal source and saidfirst electrode means for varying the amplitude of the output pulses provided by the said first pulsesig'nal source, and wherein'the'pulses of said 40 series of pulses Lhave relative amplitudes determined by the saidarnplitude varying 'means. 7 5. .A pulse delay circuit asfc la irned in claim "5, where- .in said amplitude varying'nreans'com rises variable impedance means. 7. 'A pulse delay circuit including a signal translation device "com rising anelon'ga't ed bodylof semiconduciive material of predetermined conductivity type having oplposi'te e ndpdrtions surface persons between said emptiness, aj mina artmas larinatenn of opposite Iconduc ivit'y type spaced apart and arranged on "said surface? portions, first ,lectrodeme'ans in contact with one of said zones, second electro'de lmeansiin contact with at leastitwo of saidflz ones' spaced apart from said firstmentioned zone, and a pair of base electrodes in low .tresistancejcont ajctwith said oppositeiend portions, afirst pulse signal sourcefconnected to said first electrode means, second "punesignar'seum connected .to said base electrodes, and output pulse deriving means connectedlto said secondf electrode m eans providing an outiput ignal comprising a s eries of pulses clorr'e spondingtto the pulsesprovided lbyjsaid first pulsesignal sour esuper- V imposed jjr on; e pulse provided said second pan aerial. eq ate t me anemia ea .-I i I said series "of pulses after the initialfpulseproduced hy fle -se fittt-2 l a s al so c -fi ms. d h

with tli relative spacing of isaidi'first andT's'econd elec- 'trode nine ans V delay aim "t"asfeiainea ne aim 1; ai maa Y 53 between sai 5? e and said mutpiit pulse derivinglineansdf or f the-output -si gnal.pulses, and E j ul sa iu r :fi et he re e amplitudes determined by the lsaid :amplitude varying m ans. t a

Qui t-pulse delay circuitraswlaimed'in claim 8, wherein said amplitude varying means comprises variable impedance means.

10. A pulse delay circuit including a signal translation device comprising an elongated body of semiconductive material of predetermined conductivity type having opposite end portions and surface portions between said end portions, a plurality of zones of material of opposite conductivity type spaced apart and arranged on said surface portions, first electrode means in contact with at least two of said zones, second electrode means in contact with one of said zones spaced apart from said firstmentioned zones, and a pair of base electrodes in low resistance contact with said opposite end portions, a first pulse signal source connected to said first electrode means, a second signal source connected to said base electrodes, and output pulse deriving means connected to said second electrode means providing an output signal comprising a series of pulses corresponding to the pulses provided by said first pulse signal source superimposed upon the signal provided by said second signal source, the time of occurrence of each pulse of said series of pulses after the initial pulse produced by the said first pulse signal source varying in accordance with the relative spacing of said first and second electrode means.

II. A pulse delay circuit as claimed in claim 10, further comprising means interposed between said first pulse signal source and said first electrode means for varying the amplitude of the output pulses provided by the said first pulse signal source, and wherein the pulses of said series of pulses have relative amplitudes determined by the said amplitude varying means.

12. A pulse delay circuit as claimed in claim 11, wherein said amplitude varying means comprises variable impedance means.

References Cited in the file of this patent UNITED STATES PATENTS 2,476,323 Rack July 19, 1949 2,600,500 Haynes et a1. June 17, 1952 2,655,607 Reeves Oct. 13, 1953 2,701,302 Giacoletto Feb. ,1, 1955 2,702,838 Haynes Feb. 22, 1955 2,761,020 Shockley Aug. 28, 1956 2,769,926 Lesk Nov. 6, 1956 2,801,348 Pankove July 30, 1957 2,832,898 Camp Apr. 29, 1958 

